A traditional connector of a microphone is assembled through the following processes. An internal assembly (pin insert) including connector pins and electronic parts is inserted into a cylindrical connector case. After this step, the connector case is tightened with screws toward the internal assembly from the exterior in the radial direction of the connector case. The internal assembly is fixed in the connector case through these processes.
In such a connector of a microphone, the connector case is tightened with screws toward the internal assembly from the exterior in the radial direction of the connector case; hence, the connector pins of the internal assembly are pulled in the axial directions of the screws.
As a result, the connector of the microphone may cause the eccentricity or rotation of the pin insert, leading to the displacement of the connector pins from a predetermined position. In this case, the traditional connector of the microphone causes no contact of the connector pins or no engagement in the connection between the male and female connectors.
A condenser microphone includes electronic circuits, such as a detecting unit (microphone unit) for detecting vibration of air, an impedance converter, or an output circuit, which include electronic parts.
Electric signals detected in the detecting unit have high impedance. In order to avoid the influence of noise, the impedance converter must convert high impedance electric signals into low impedance electric signals and efficiently output the signals.
For example, a microphone cord is exposed to strong electromagnetic waves to cause a high frequency current to flow into the microphone through the connector of the microphone. The flow of the high frequency current is detected by circuit elements in the electronic circuits to cause noise in audio signals.
Techniques are disclosed for preventing the eccentricity or rotation of a pin insert fit into a connector case in assembly processes of a microphone (for example, see Japanese Unexamined Patent Application Publications Nos. 2008-141575 (Patent Literature 1) and 2008-67341 (Patent Literature 2)).
Other techniques are disclosed for providing an electrostatic shield over a connector for prevention of noise in a condenser microphone (for example, see Japanese Unexamined Patent Application Publications Nos. 2005-094575 (Patent Literature 3) and 2011-205179 (Patent Literature 4)).
Unfortunately, the techniques disclosed in Patent Literatures 1 and 2 also involve the connector case tightened with the screws toward the pin insert from the exterior in the radial direction of the connector case. As a result, the connector pins are pulled in the axial directions of the screws. In other words, the displacement of the pin insert in the techniques disclosed in Patent Literatures 1 and 2 also causes no contact of the connector pins or no engagement in the connection between the male and female connectors.
In addition, the techniques disclosed in Patent Literatures 3 and 4 require an additional shielding component, such as a magnetic sheet for an electrostatic shield over the connector to therefore increase the numbers of the components and the assembly steps.